1. Field of the Invention
This invention relates to call simulators for PSTN-IP network telephone services and methods of operation. More particularly, the invention relates to a client""s simulator and method of operation in testing PSTN to IP network telephone services for individual and group internet clients prior to availability of the telephone services.
2. Description of Prior Art
The introduction of PSTN-IP network based telephone services, e.g., call waiting, call forwarding, call back, etc., requires PSTN or IP network service providers to verify and validate these new services before on-line operations commence. The verification and validity involves generating hundreds of telephone calls per second and simulating thousands of IP network clients as individuals or group internet clients. What is needed to verify or validate a service is a call simulator, which simulates client behavior in groups or individuals to the telephone system in a test system for testing telephone services prior to the availability of the telephone services to the subscribers and clients.
Prior art related to client simulators for testing telephone services includes the following:
U.S. Pat. No. 3,952,172 entitled xe2x80x9cTelephone Call simulatorxe2x80x9d, issued Apr. 20, 1976, discloses a telephone simulator, which includes a plurality of pseudo-subscriber circuits connected to subscriber lines. A plurality of pseudo junctures are connected to trunk lines. A number of detector circuits respond to line conditions, tones, circuit operations, data processing, and the like. A data processor uses this equipment to check incoming and outgoing calls to and from a public telephone network.
U.S. Pat. No. 4,238,649 entitled xe2x80x9cCall Simulatorxe2x80x9d, issued Dec. 9, 1980, discloses a traffic simulator for simulating calls switched through a tandem exchange by simulating both the calling and the answering exchange sides of signaling with the tandem exchange, and in which the progress of the call is split into a succession of phases during which a connection is set up through the tandem exchange, speech between subscribers is simulated, and the connection is cleared. A simulator comprises two independent modules, a calling side module connected to an incoming circuit terminating equipment of the exchange to simulate signaling between a calling exchange and the tandem exchange by its incoming circuit connected to the incoming terminating equipment and answering side module connected to an outgoing circuit terminating equipment of the exchange to simulate signaling between the tandem exchange and an answering exchange.
U.S. Pat. No. 5,065,422 entitled xe2x80x9cSubscriber Call Simulator Capable of Testing New Services of a Telephone Switching Systemxe2x80x9d, issued Nov. 12, 1991, discloses a subscriber call simulator connected to a telephone switching system through subscriber lines and acting as a plurality of pseudo-subscriber telephone sets. An input/output section, inputs control procedure information for the pseudo-subscriber""s telephone sets. Connected to the input/output section is a memorizing arrangement, which memorizes the control procedure information as stored information. By using the stored information, a control circuit controls the pseudo-subscriber""s telephone sets. The control procedure information comprises a control procedure program and correspondence information stored in a procedure program memory in a correspondence information memory, respectively, both of which act as the memorizing arrangement for automatically testing various new telephone services.
None of the prior art discloses a PSTN-IP network based client simulator for simulating individual and group internet clients for PSTN-IP network telephone services prior to the availability of the telephone services.
An object of the invention is a call simulator and method of operation for use in testing PSTN to IP network telephone services.
Another object is a call simulator and method of operation simulating thousands of IP network clients doing testing of PSTN-IP telephone services.
Another object is a call simulator and method of operation providing a mix of predictable client responses during testing of PSTN-IP telephone services.
Another object is a call simulator and method of operation, which provides separate and distinct, simulated client actions during testing of PSTN-IP telephone services.
These and other objects, features and advantages are achieved in a client simulator including a processor coupled to a TCP/IP data network linked to a PSTN via a System Control Point (SCP) and to an IP network via an application server. A storage means is coupled to the processor through input/output registers and includes stored instructions for a parent process in a plurality of client processes in a client pool. The parent process is responsible for reading a test input data file and passing the client process behavior profile to the client process. Each client process is responsible for returning state information to the PSTN; call handling actions and providing call handling statistics. The client process includes a client behavior control function, which processes and maintains behavior parameters passed by the client parent process. The behavior function, inter alia, accepts the call message; forwards the call message according to the client behavior profile. The client process further includes a send/receive function to read and write to the registers coupled to the TCP/IP data network and support voice over IP protocols. A test originated by the PSTN is passed by the SCP and application file to the client simulator. A parent processes in the simulator reads a test input data file and passes the call message to the client process. The client process provides a variety of call handling options including (a) accepting the call when a client""s PC forwarding the call to another number; sending a voice message to the caller. The call data message responses are sent back to the SCP through the application server. The SCP directs the PSTN on how to handle the message call response.